The present invention relates to apparatus for supporting the seat of a bicycle on a bicycle frame, more particularly to such apparatus for absorbing road impact shocks otherwise transmittable from the frame to the seat, and most particularly to such shock-absorbing apparatus wherein the length of a shock-absorbing strut may be varied at will by a rider to vary the distance between the seat and the bicycle pedals or the ground.
Conventional bicycles in common use today typically have a rigid tubular frame to which are attached a front wheel which is pivotable via handlebars for steering, a sprocketed rear wheel, a pedaled sprocket and continuous chain for driving the rear wheel, and a seat for a single rider. Such seats, especially those intended for touring and/or racing competition, typically are narrow and hard, affording little isolation and protection for the rider from road shocks, which can cause muscle fatigue and nerve damage.
Further, in conventional bicycles, the seat typically is mounted on a rod which extends downwards into a seat-supporting tubular member of the frame wherein the rod is captured and held by a bolted clamp to fixedly retain the seat at a desired distance from the pedals. Optimally, this distance to a lower pedal is approximately the full leg extension of the rider; thus, to avoid falling over when stopping, the rider must leave a seated position and stand on one pedal while removing the other leg from the other pedal and extending the other leg to the ground. There is no means in conventional bicycles whereby the rider may vary at will the distance from the seat to the pedals or to the ground while remaining seated.
In the prior art, the absorption of road shocks is addressed in one of two ways, either by resiliently articulating the bicycle frame such that shocks are absorbed by flexing of the frame before reaching the rider, or by allowing a rigid frame to receive the shocks but isolating the rider from the frame, or by a combination of the two.
U.S. Pat. No. 5,356,165 issued Oct. 19, 1994, and U.S. Pat. No. 5,498,014 issued Mar. 12, 1996, both to Kulhawik et al., disclose a bicycle suspension wherein the rear wheel and a pedaled sprocket are mounted to a rigid rear frame, and the front wheel is mounted to a conventional pivotable fork in a rigid front frame pivotably and shock-absorbingly connected to the rear frame at a forward end thereof, the seat being rigidly mounted on a rearward extension of the front frame.
U.S. Pat. No. 5,611,557 issued Mar. 18, 1997 to Farris et al. discloses a bicycle suspension system wherein the front wheel is mounted to a conventional pivotable fork in a rigid front frame which also supports a pedaled sprocket, the rear wheel is mounted to a rigid rear frame pivotably connected to the front frame forward of the sprocket, and the seat is mounted on a beam pivotably connected to both the front frame and the rear frame via an action comprising a walking beam, various lever arms, and a shock absorber.
U.S. Pat. No. 5,752,227 issued Mar. 10, 1998 to Mayer discloses an action similar to that of Farris et al. wherein the seat mounting means is actuably connected to both a front frame and a rear frame.
U.S. Pat. No. 4,934,724 issued Jun. 10, 1990; U.S. Pat. No. 5,029,888 issued Jul. 9, 1991; and U.S. Pat. No. 5,240,268 issued Aug. 31, 1993, all to Allsop et al., disclose a bicycle having a substantially rigid frame, the seat support post being omitted and the seat being mounted at the rear end of a flexible shock-absorbing beam attached at its forward end to, and extending freely in space and rearwardly from, the frame at a point behind the front fork.
My U.S. Pat. No. 5,829,733 ('733) issued Nov. 3, 1998, the disclosure of which is hereby incorporated herein by reference, discloses a shock absorbing and adjustable height bicycle seat mounting assembly for installation onto or into a bicycle frame vertical seat support member. The assembly comprises a gas spring and an actuator which may be remotely adjusted by a rider at will to change the height of the seat, as for mounting and dismounting the bicycle and for optimizing the riding position, without altering the shock-absorbing capability of the assembly.